What the ratings mean for your panel
The Siemens 3VA2225-5JQ32-0DE0 is a 3-pole IEC frame 250 molded-case circuit breaker with a breaking capacity class M rating of Icu=55kA at 415V AC. That 55 kA interrupting rating at 415V is the ultimate short-circuit capacity — the breaker can safely clear a fault up to that level once and still be operable afterward. For a 400V industrial distribution board fed by a transformer in the 1.5–2 MVA range, that's enough headroom to avoid cascading upstream. The ETU560 electronic trip unit gives you LSIG protection: long-time (overload), short-time (short-circuit with adjustable delay), instantaneous, and ground-fault. In=250A, with overload protection Ir adjustable from 100A to 250A, short-circuit protection ISD from 0.6 to 10×In, and instantaneous pickup II from 1.5 to 10×In. Ground-fault protection can be switched off, with IG adjustable 0.2 to 1×In and time delay TG at 0.05 or 0.8 seconds. The built-in undervoltage release (208–230V AC 50/60 Hz) and four auxiliary switches round out the package for remote status and shunt-trip capability.
Deployment context
The 3VA2 frame mounts in a standard panel or enclosure on a DIN rail or bolted busbar system. The ETU560 LSIG trip unit is field-adjustable, so you can dial in the protection curve to match downstream loads without swapping the breaker. The undervoltage release (208–230V AC) provides automatic trip on loss of control voltage — typical for safety circuits or emergency-stop chains. The four auxiliary switches give status feedback to a PLC or SCADA for remote indication of breaker position.
